@article{HaarmannVollmuthKollikowskietal.2023,
  author    = {Haarmann, Axel and Vollmuth, Christoph and Kollikowski, Alexander M. and Heuschmann, Peter U. and Pham, Mirko and Stoll, Guido and Neugebauer, Hermann and Schuhmann, Michael K.},
  title     = {Vasoactive soluble endoglin: a novel biomarker indicative of reperfusion after cerebral large-vessel occlusion},
  series = {Cells},
  volume    = {12},
  journal   = {Cells},
  number    = {2},
  issn      = {2073-4409},
  doi       = {10.3390/cells12020288},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-304995},
  year      = {2023},
  abstract  = {Now that mechanical thrombectomy has substantially improved outcomes after large-vessel occlusion stroke in up to every second patient, futile reperfusion wherein successful recanalization is not followed by a favorable outcome is moving into focus. Unfortunately, blood-based biomarkers, which identify critical stages of hemodynamically compromised yet reperfused tissue, are lacking. We recently reported that hypoxia induces the expression of endoglin, a TGF-β co-receptor, in human brain endothelium in vitro. Subsequent reoxygenation resulted in shedding. Our cell model suggests that soluble endoglin compromises the brain endothelial barrier function. To evaluate soluble endoglin as a potential biomarker of reperfusion (-injury) we analyzed its concentration in 148 blood samples of patients with acute stroke due to large-vessel occlusion. In line with our in vitro data, systemic soluble endoglin concentrations were significantly higher in patients with successful recanalization, whereas hypoxia alone did not induce local endoglin shedding, as analyzed by intra-arterial samples from hypoxic vasculature. In patients with reperfusion, higher concentrations of soluble endoglin additionally indicated larger infarct volumes at admission. In summary, we give translational evidence that the sequence of hypoxia and subsequent reoxygenation triggers the release of vasoactive soluble endoglin in large-vessel occlusion stroke and can serve as a biomarker for severe ischemia with ensuing recanalization/reperfusion.},
  language  = {en}
}
@article{HerzbergDornTrummetal.2022,
  author    = {Herzberg, Moriz and Dorn, Franziska and Trumm, Christoph and Kellert, Lars and Tiedt, Steffen and Feil, Katharina and K{\"u}pper, Clemens and Wollenweber, Frank and Liebig, Thomas and Zimmermann, Hanna},
  title     = {Middle cerebral artery M2 thrombectomy: safety and technical considerations in the German Stroke Registry (GSR)},
  series = {Journal of Clinical Medicine},
  volume    = {11},
  journal   = {Journal of Clinical Medicine},
  number    = {15},
  issn      = {2077-0383},
  doi       = {10.3390/jcm11154619},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-286052},
  year      = {2022},
  abstract  = {There is ongoing debate concerning the safety and efficacy of various mechanical thrombectomy (MT) approaches for M2 occlusions. We compared these for MT in M2 versus M1 occlusions. Subgroup analyses of different technical approaches within the M2 MT cohort were also performed. Patients were included from the German Stroke Registry (GSR), a multicenter registry of consecutive MT patients. Primary outcomes were reperfusion success events. Secondary outcomes were early clinical improvement (improvement in NIHSS score > 4) and independent survival at 90 days (mRS 0-2). Out of 3804 patients, 2689 presented with M1 (71\%) and 1115 with isolated M2 occlusions (29\%). The mean age was 76 (CI 65-82) and 77 (CI 66-83) years, respectively. Except for baseline NIHSS (15 (CI 10-18) vs. 11 (CI 6-16), p < 0.001) and ASPECTS (9 (CI 7-10) vs. 9 (CI 8-10, p < 0.001), baseline demographics were balanced. Apart from a more frequent use of dedicated small vessel stent retrievers (svSR) in M2 (17.4\% vs. 3.0; p < 0.001), intraprocedural aspects were balanced. There was no difference in ICH at 24 h (11\%; p = 1.0), adverse events (14.4\% vs. 18.1\%; p = 0.63), clinical improvement (62.5\% vs. 61.4 \%; p = 0.57), mortality (26.9\% vs. 22.9\%; p = 0.23). In M2 MT, conventional stent retriever (cSR) achieved higher rates of mTICI3 (54.0\% vs. 37.7-42.0\%; p < 0.001), requiring more MT-maneuvers (7, CI 2-8) vs. 2 (CI 2-7)/(CI 2-2); p < 0.001) and without impact on efficacy and outcome. Real-life MT in M2 can be performed with equal safety and efficacy as in M1 occlusions. Different recanalization techniques including the use of svSR did not result in significant differences regarding safety, efficacy and outcome.},
  language  = {en}
}
@article{SchuhmannGunrebenKleinschnitzetal.2016,
  author    = {Schuhmann, Michael K. and Gunreben, Ignaz and Kleinschnitz, Christoph and Kraft, Peter},
  title     = {Immunohistochemical Analysis of Cerebral Thrombi Retrieved by Mechanical Thrombectomy from Patients with Acute Ischemic Stroke},
  series = {International Journal of Molecular Sciences},
  volume    = {17},
  journal   = {International Journal of Molecular Sciences},
  number    = {3},
  doi       = {10.3390/ijms17030298},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166206},
  pages     = {298},
  year      = {2016},
  abstract  = {Mechanical thrombectomy is a novel treatment option for patients with acute ischemic stroke (AIS). Only a few studies have previously suggested strategies to categorize retrieved clots according to their histologic composition. However, these reports did not analyze potential biomarkers that are of importance in stroke-related inflammation. We therefore histopathologically investigated 37 intracerebral thrombi mechanically retrieved from patients with AIS, and focused on the composition of immune cells and platelets. We also conducted correlation analyses of distinctive morphologic patterns (erythrocytic, serpentine, layered, red, white, mixed appearance) with clinical parameters. Most T cells and monocytes were detected in erythrocytic and red clots, in which the distribution of these cells was random. In contrast, von Willebrand factor (vWF)-positive areas co-localized with regions of fibrin and collagen. While clots with huge amounts of vWF seem to be associated with a high National Institute of Health Stroke Scale score at admission, histologic findings could not predict the clinical outcome at discharge. In summary, we provide the first histologic description of mechanically retrieved intracerebral thrombi regarding biomarkers relevant for inflammation in ischemic stroke.},
  language  = {en}
}
@article{StrinitzPhamMaerzetal.2021,
  author    = {Strinitz, Marc and Pham, Mirko and M{\"a}rz, Alexander G. and Feick, J{\"o}rn and Weidner, Franziska and Vogt, Marius L. and Essig, Fabian and Neugebauer, Hermann and Stoll, Guido and Schuhmann, Michael K. and Kollikowski, Alexander M.},
  title     = {Immune cells invade the collateral circulation during human stroke: prospective replication and extension},
  series = {International Journal of Molecular Sciences},
  volume    = {22},
  journal   = {International Journal of Molecular Sciences},
  number    = {17},
  issn      = {1422-0067},
  doi       = {10.3390/ijms22179161},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284281},
  year      = {2021},
  abstract  = {It remains unclear if principal components of the local cerebral stroke immune response can be reliably and reproducibly observed in patients with acute large-vessel-occlusion (LVO) stroke. We prospectively studied a large independent cohort of n = 318 consecutive LVO stroke patients undergoing mechanical thrombectomy during which cerebral blood samples from within the occluded anterior circulation and systemic control samples from the ipsilateral cervical internal carotid artery were obtained. An extensive protocol was applied to homogenize the patient cohort and to standardize the procedural steps of endovascular sample collection, sample processing, and laboratory analyses. N = 58 patients met all inclusion criteria. (1) Mean total leukocyte counts were significantly higher within the occluded ischemic cerebral vasculature (I) vs. intraindividual systemic controls (S): +9.6\%, I: 8114/µL ± 529 vs. S: 7406/µL ± 468, p = 0.0125. (2) This increase was driven by neutrophils: +12.1\%, I: 7197/µL ± 510 vs. S: 6420/µL ± 438, p = 0.0022. Leukocyte influx was associated with (3) reduced retrograde collateral flow (R\(^2\) = 0.09696, p = 0.0373) and (4) greater infarct extent (R\(^2\) = 0.08382, p = 0.032). Despite LVO, leukocytes invade the occluded territory via retrograde collateral pathways early during ischemia, likely compromising cerebral hemodynamics and tissue integrity. This inflammatory response can be reliably observed in human stroke by harvesting immune cells from the occluded cerebral vascular compartment.},
  language  = {en}
}
@article{VogtKollikowskiWeidneretal.2022,
  author    = {Vogt, Marius L. and Kollikowski, Alexander M. and Weidner, Franziska and Strinitz, Marc and Feick, J{\"o}rn and Essig, Fabian and Neugebauer, Herrmann and Haeusler, Karl Georg and Pham, Mirko and Maerz, Alexander},
  title     = {Safety and Effectiveness of the New Generation APERIO® Hybrid Stent-retriever Device in Large Vessel Occlusion Stroke},
  series = {Clinical Neuroradiology},
  volume    = {32},
  journal   = {Clinical Neuroradiology},
  number    = {1},
  doi       = {10.1007/s00062-021-01122-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-264817},
  pages     = {141-151},
  year      = {2022},
  abstract  = {Background It is unknown whether technological advancement of stent-retriever devices influences typical observational indicators of safety or effectiveness. Methods Observational retrospective study of APERIO® (AP) vs. new generation APERIO® Hybrid (APH) (Acandis®, Pforzheim, Germany) stent-retriever device (01/2019-09/2020) for mechanical thrombectomy (MT) in large vessel occlusion (LVO) stroke. Primary effectiveness endpoint was successful recanalization eTICI (expanded Thrombolysis In Cerebral Ischemia) ≥ 2b67, primary safety endpoint was occurrence of hemorrhagic complications after MT. Secondary outcome measures were time from groin puncture to first pass and successful reperfusion, and the total number of passes needed to achieve the final recanalization result. Results A total of 298 patients with LVO stroke who were treated by MT matched the inclusion criteria: 148 patients (49.7\%) treated with AP vs. 150 patients (50.3\%) treated with new generation APH. Successful recanalization was not statistically different between both groups: 75.7\% for AP vs. 79.3\% for APH; p = 0.450. Postinterventional hemorrhagic complications and particularly subarachnoid hemorrhage as the entity possibly associated with stent-retriever device type was significantly less frequent in the group treated with the APH: 29.7\% for AP and 16.0\% for APH; p = 0.005; however, rates of symptomatic hemorrhage with clinical deterioration and in domo mortality were not statistically different. Neither the median number of stent-retriever passages needed to achieve final recanalization, time from groin puncture to first pass, time from groin puncture to final recanalization nor the number of cases in which successful recanalization could only be achieved by using a different stent-retriever as bail-out device differed between both groups. Conclusion In the specific example of the APERIO® stent-retriever device, we observed that further technological developments of the new generation device were not associated with disadvantages with respect to typical observational indicators of safety or effectiveness.},
  language  = {en}
}